My 2002 Tacoma 3.4 check engine light came on, had it checked and it showed a P1135 code. I drove it for awhile with the light on; it came on when the engine heated up, but when it began to stay on constantly I changed the front AF sensor. The engine was running rough at low speed, and progressively got worse until I changed it. It still hesitates when I leave an intersection. Could the plugs have gotten fouled and need changing? It runs great in all other ranges. Any suggestions would be welcomed. Thanks

 

It's not hestitating at night in cooler weather....WTH.